Phytic acid, the most abundant “inositol phosphate” (Ins P) in nature, is synthesized in all cells but high rates of synthesis are observed in seeds. In cereals grains phytic acid is synthesized in both the germ/embryo and aleurone. In an experiment searching for the barley Lpa1 gene, Mapping work and genomic characterization in the chromosomal region in Lpa1 mutant, another related gene in phytic acid metabolism, Ins polyphosphate 2-kinase, has been identified. Southern blot analyses indicated the barley genome contains one copy of this gene. Expression patterns of the Ins polyphosphate 2-kinase gene indicate that this gene is constitutively expressed in all tissues but that the promoter has seed-specific or seed-enhancing elements.